P4D21

P4D21 Ford engine fault code diagnosis, code meaning,symptoms and how to fix it.

P4D21 Diagnosis

The CHM does not suupport PWM type DRLs. The vehicle has a BHM mismatch with the CHM. Replace the CHM with one that is compatible with the BHM.The BHM is detecting more than one smart switch with the same ID number present on the vehicle. The outputs controlled by the switch and the indicator in the switch are commanded FF.

The End of Frame air output circuit is commanded OFF, but air pressure is detected at the pressure feedback switch. Troubleshoot for an End of Frame air solenoid fault, and for an air pressure switch short circuit fault.

Ford P4D21 Fault Code Meaning :

Ford P4D21 Symptoms :

Ford P4D21 Reasons :

How To Fix Ford P4D21 Trouble Code ?

Which Ford cars have the code P4D21?

  • P4D21 Ford Aerostar
  • P4D21 Ford Bronco
  • P4D21 Ford C-Max
  • P4D21 Ford C-Max Energi
  • P4D21 Ford C-Max Hybrid
  • P4D21 Ford Contour
  • P4D21 Ford Crown Victoria
  • P4D21 Ford EcoSport
  • P4D21 Ford Econoline
  • P4D21 Ford Edge
  • P4D21 Ford Escape
  • P4D21 Ford Escape Hybrid
  • P4D21 Ford Escort
  • P4D21 Ford Everest
  • P4D21 Ford Excursion
  • P4D21 Ford Expedition
  • P4D21 Ford Explorer
  • P4D21 Ford Explorer Sport Trac
  • P4D21 Ford F-150
  • P4D21 Ford F-250
  • P4D21 Ford F-350
  • P4D21 Ford Fiesta
  • P4D21 Ford Flex
  • P4D21 Ford Focus
  • P4D21 Ford Focus Electric
  • P4D21 Ford Freestar
  • P4D21 Ford Freestyle
  • P4D21 Ford Fusion
  • P4D21 Ford Fusion Energi
  • P4D21 Ford Fusion Hybrid
  • P4D21 Ford Fusion Plug-In Hybrid
  • P4D21 Ford GT
  • P4D21 Ford Mustang
  • P4D21 Ford Mustang Mach-E
  • P4D21 Ford Mystique
  • P4D21 Ford Probe
  • P4D21 Ford Ranger
  • P4D21 Ford Taurus
  • P4D21 Ford Taurus X
  • P4D21 Ford Tempo
  • P4D21 Ford Thunderbird
  • P4D21 Ford Transit
  • P4D21 Ford Transit Connect
  • P4D21 Ford Windstar

A code is a fault code and it indicates that something has gone wrong with your car's engine.

It can be caused by many different problems, including a faulty battery, a bad fuel pump, or even a cracked exhaust manifold.

You will need to diagnose the problem before you can fix it. The best way to do this is with an OBD scanner tool.

A scan tool will tell you what needs fixing and how much it will cost in order to fix that particular issue.